Wireless communication system, device, and control method for searching multiple communication frequency channels and processing cryptographic communication in an infrastructure mode using a received communication parameter including information of an encrypted key

ABSTRACT

This invention has as its object to set a one-to-one relationship upon establishing a wireless communication channel between a wireless communication device on the information transmitting side and a wireless communication device that receives and processes the information even in an environment including a plurality of wireless communication devices, and to assure simple user&#39;s operations at least until the communication channel is established. To this end, when the user inputs a wireless communication channel establishment instruction to both a digital camera and printer having wireless communication functions, these devices execute wireless communication establishment processes within an allowable time period which is specified by a time set in a timer and a retry count. When the devices can seize each other within that time period, the communication channel is established. After that, the digital camera sends a sensed image to the printer, which prints the sensed image.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 13/541,190, filed Jul. 3, 2012, which is a continuation U.S.patent application Ser. No. 12/968,131, filed Dec. 14, 2010, which is acontinuation of U.S. patent application Ser. No. 10/551,175, filed Sep.29, 2005, now U.S. Pat. No. 7,882,234, which is a U.S. National StageEntry of International Application No. PCT/JP2004/005588, filed Apr. 20,2004, which claims priority to Japan Patent Application No. 2003-119052,filed Apr. 23, 2003. The entire disclosure of each prior application isincorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a communication establishment techniquebetween devices having wireless communication functions.

BACKGROUND ART

Normally, a host computer as a versatile information processingapparatus such as a personal computer or the like and a printer areconnected by wire. Such wired connection adopts a USB cable, parallelcable (complying with the Centronics standards (USA)), Ethernet, and thelike.

In recent years, digital cameras have prevailed increasingly, and therecording quality of printers has improved as high as silver halidephotos. Hence, there are many chances of printing images sensed by suchdigital camera by printers.

In order to print an image sensed by a digital camera, it is a commonpractice to transfer that image to a personal computer, and to print itby operating an application program that runs on the personal computer.

However, a digital camera user requires a personal computer when he orshe wants to print sensed images, and much time and labor are requiredfrom when the user turns on the personal computer until he or shelaunches an application to print an image. Hence, such processes are farfrom an easy print process.

In consideration of such situation, the present applicant has proposedsome techniques that directly connect a printer and digital camera bywire.

However, since such wired connection requires a connection cable as amatter of course, a demand has arisen for wireless informationtransmission, and wireless communications have begun to be used incommunications between peripheral devices (e.g., a printer and digitalcamera).

Hence, the current connection method of wireless communication devicesbetween peripheral devices will be explained first.

Note that expression “establish a communication channel” in thefollowing description means not only to set a wireless link but also toestablish a logical channel (network layer or transport layer in the OSIreference model) to allow data communications between devices.

FIG. 25 is a flow chart showing the conventional method for searchingfor a printer to which data is to be transmitted from a digital camerawhen the adhoc mode of a wireless LAN is used as wireless communicationmeans. FIG. 25 shows a flow chart executed when a new digital camera isbrought into an existing wireless LAN communication system in the adhocmode, and establishes connection to the printer.

Referring to FIG. 25, when the digital camera is connected to theprinter in the adhoc mode, an ESSID (Extend Service Set Identify) is setin the digital camera (step S2501), a channel used in a wirelesscommunication is set (step S2502), the adhoc mode as a wirelesscommunication mode is set (step S2503), and devices on the wirelessnetwork are searched (step S2504). Then, the user selects a printer tobe used in a print process from the devices on the wireless network(step S2505), thus establishing a communication channel.

However, in such prior art, since a plurality of partners of wirelesscommunications may be found, a selection process is indispensable evenwhen only one partner is found.

DISCLOSURE OF INVENTION

The present invention has been made in consideration of the abovesituation, and has as its object to provide a technique that can raisethe possibility that the transmitting and receiving sides have aone-to-one relationship even in an environment in which there are aplurality of wireless communication devices, and can simplify a user'sselection operation.

In order to achieve the above object, a wireless communication systemaccording to the present invention comprises the following arrangement.That is, there is provided a wireless communication system whichcomprises a first wireless communication device that stores informationto be transmitted, and a second wireless communication device thatreceives the information and applies a predetermined process to theinformation, wherein each of the first and second wireless communicationdevices comprises: determination means for determining whether or not awireless communication channel establishment instruction is detected;and communication establishment means for, when the determination meansdetermines that the wireless communication channel establishmentinstruction is detected, executing a process for establishing a wirelesscommunication within a predetermined time period, and when acommunication channel is established by the communication establishmentmeans of the first and second wireless communication devices, the firstwireless communication device transmits information to the secondwireless communication device, which applies the predetermined processto the received information.

Other features and advantages of the present invention will be apparentfrom the following description taken in conjunction with theaccompanying drawings, in which like reference characters designate thesame or similar parts throughout the figures thereof.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram showing a network of wireless communication devicesin an embodiment of the present invention;

FIG. 2 is a diagram showing another network of wireless communicationdevices in an embodiment of the present invention;

FIG. 3 is a block diagram showing the arrangement of a digital cameraaccording to an embodiment of the present invention;

FIG. 4 is a block diagram showing the arrangement of a printer accordingto an embodiment of the present invention;

FIG. 5 is a block diagram showing the arrangement of a storage deviceaccording to an embodiment of the present invention;

FIG. 6 is a flow chart showing a wireless communication establishmentprocess sequence of a wireless communication device according to thefirst embodiment of the present invention;

FIG. 7 is a flow chart showing another wireless communicationestablishment process sequence of a wireless communication deviceaccording to the first embodiment of the present invention;

FIG. 8 is a flow chart showing still another wireless communicationestablishment process sequence of a wireless communication deviceaccording to the first embodiment of the present invention;

FIG. 9 is a flow chart showing yet another wireless communicationestablishment process sequence of a wireless communication deviceaccording to the first embodiment of the present invention;

FIG. 10 is a flow chart showing a processing sequence of the digitalcamera according to the first embodiment of the present invention;

FIG. 11 is a flow chart showing a processing sequence of the printeraccording to the first embodiment of the present invention;

FIG. 12 is a flow chart showing another processing sequence of theprinter according to the first embodiment of the present invention;

FIG. 13 is a diagram showing an example of the arrangement of a wirelesscommunication system according to the second embodiment of the presentinvention;

FIG. 14 is a diagram showing another example of the arrangement of awireless communication system according to the second embodiment of thepresent invention;

FIG. 15 is a flow chart showing a control process sequence of a wirelesscommunication device according to the second embodiment of the presentinvention;

FIG. 16 is a flow chart showing another control process sequence of awireless communication device according to the second embodiment of thepresent invention;

FIG. 17 is a flow chart showing a control process sequence of a wirelesscommunication device according to the third embodiment of the presentinvention;

FIG. 18 is a flow chart showing another control process sequence of awireless communication device according to the third embodiment of thepresent invention;

FIG. 19 is a flow chart showing another control process sequence of awireless communication device on the transmitting side according to thethird embodiment of the present invention;

FIG. 20 is a flow chart showing another control process sequence of awireless communication device on the receiving side according to thethird embodiment of the present invention;

FIG. 21 is a flow chart showing still another control process sequenceof a wireless communication device on the transmitting side according tothe third embodiment of the present invention;

FIG. 22 is a flow chart showing still another control process sequenceof a wireless communication device on the receiving side according tothe third embodiment of the present invention;

FIG. 23 is a flow chart showing another control process sequence of awireless communication device on the transmitting side according to thefourth embodiment of the present invention;

FIG. 24 is a flow chart showing another control process sequence of awireless communication device on the receiving side according to thefifth embodiment of the present invention; and

FIG. 25 is a flow chart showing the control of a conventional wirelesscommunication device.

BEST MODE FOR CARRYING OUT THE INVENTION

Respective embodiments according to the present invention will bedescribed hereinafter with reference to the accompanying drawings.

First Embodiment

The first embodiment will explain an example that can facilitate searchand selection processes of a partner communication device with which acommunication channel is to be established in an environment in whichnetwork-related setups have already been done.

FIG. 1 shows an example of the arrangement of a wireless communicationsystem that allows data transmission using wireless communication means.Referring to FIG. 1, digital cameras 101 to 103 comprise a wirelesscommunication function, and can make direct data communications usingthe wireless communication means among themselves or with printers 104and 105. A communication mode of such configuration will be referred toas an adhoc mode hereinafter.

FIG. 2 shows another example of the arrangement of a wirelesscommunication system that allows data transmission using wirelesscommunication means. Referring to FIG. 2, digital cameras 201 to 203comprise a wireless communication function, and can make datacommunications using the wireless communication means among themselvesor with a printer 205 or storage 206. This data communication is madevia an access point 204. A communication mode of such configuration willbe referred to as an infrastructure mode hereinafter.

The digital camera, printer, and storage in this embodiment will beexplained in turn.

FIG. 3 is a functional block diagram showing the functional blocks of adigital camera 301, which can serve as one of the digital cameras 101 to103 or 201 to 203 shown in FIGS. 1 and 2.

A console 310 of the digital camera is connected to a CPU 315 via asystem controller 311, and comprises a shutter switch and various keysof the digital camera. An image sensing unit 302 is a block that sensesan image upon depression of the shutter, and is processed by an imagesensing processor 303. A display unit 306 is a block that presentsinformation to the user by means of, for example, LCD display, LEDindication, audio presentation, and the like, and its displayed contentsundergo a control process by a display processor 307. An operation forselecting information from the displayed contents on the display unit306 is made in cooperation with the console 310. That is, the displayunit 306 and console 310 form a user interface.

A wireless communication function unit 304 is a block that makeswireless communications, and an RF unit 305 exchanges a wireless signalwith another wireless communication device. A memory card I/F 308 is aninterface used to connect a memory card 309, a USB I/F 312 is aninterface used to connect an external device using USB, and an audio I/F314 is an interface used to connect an audio signal with an externaldevice. These functional blocks shown in this block diagram areprocessed under the control of the CPU 315. Programs to be controlled bythe CPU are stored in a ROM 316, a flash ROM 313, or the memory card309. Data to be processed by the CPU 315 are written in or read out froma RAM 317, the flash ROM 313, or the memory card 309 (note that thesensed image data is stored in the memory card 309).

FIG. 4 is a functional block diagram showing functional blocks of aprinter 401 in this embodiment. This printer 401 can serve as theprinters 104, 105, and 205 shown in FIGS. 1 and 2.

A console 410 of the printer is connected to a CPU 415 via a systemcontroller 411. A print engine 402 is a functional block which actuallyprints an image on a paper sheet, and is processed by a print processor403. The type of print engine is not particularly limited. In thisembodiment, the print engine comprises an ink-jet printer which ejectsink drops onto a print medium such as a print sheet and the like by heatenergy.

A display unit 406 is a block which presents information to the user bymeans of LCD display, LED indication, audio presentation, and the like,and its display contents are controlled under the control of a displayprocessor 407. That is, the display unit 406 and console 410 form a userI/F of the printer 401 in this embodiment.

A wireless communication function unit 404 is a block that makeswireless communications, and an RF unit 405 exchanges a wireless signalwith another wireless communication device. A memory card I/F 408 is aninterface used to connect a detachable memory card 409. When the memorycard I/F 408 receives a memory card mounted in the digital camera, asensed image can be printed.

A USB I/F 412 is an interface used to connect an external device usingUSB, and a parallel I/F 414 is an interface used to connect an externaldevice (mainly a host computer) using a parallel communication. Thesefunctional blocks shown in this block diagram are processed under thecontrol of the CPU 415. Programs to be controlled by the CPU are storedin a ROM 416, a flash ROM 413, or the memory card 409. Data to beprocessed by the CPU are written in or read out from a RAM 417, theflash ROM 413, or the memory card 409.

FIG. 5 is a functional block diagram showing the functional blocks of astorage device 501 (to be simply referred to as a storage hereinafter)in this embodiment. This storage 501 serves as the storage 206 shown inFIG. 2.

A console 510 of the storage 501 is connected to a CPU 515 via a systemcontroller 511. A storage 502 is a functional block that stores or readsout data, and is processed by a storage processor 503. As the storage502, a large-capacity storage device, i.e., a hard disk drive, ispreferably used. In some cases, a media write drive for CD-R or CD-RWmedia, rewritable DVD media, MO media, and the like as relativelylarge-capacity, portable storage media may be used. A display unit 506is a block which presents information to the user by means of LCDdisplay, LED indication, audio presentation, and the like, and isprocessed by a display processor 507. An operation for selecting desiredone of information displayed on the display unit 506 is made via theconsole 510. That is, the display unit 506 and console 510 form a userI/F of the storage 501.

A wireless communication function unit 504 is a block that makeswireless communications, and an RF unit 505 exchanges a wireless signalwith another wireless communication device. A memory card I/F 508 is aninterface used to connect a memory card 509 (to receive a memory card ofthe digital camera and to directly save data in that card), a USB I/F512 is an interface used to connect an external device using USB, and anETHER I/F 514 is an interface used to connect an external device usingan ETHER communication. These functional blocks shown in this blockdiagram are processed under the control of the CPU 515. Programs to becontrolled by the CPU are stored in a ROM 516, a flash ROM 513, or thememory card 509. Data to be processed by the CPU are written in or readout from a RAM 517, the flash ROM 513, or the memory card 509.

The arrangements of the digital camera, printer, and storage have beenrespectively explained. Note that each RF unit has an antenna, which isnot limited to an externally protruding one. Especially, in case of thedigital camera, portability is an important factor. Hence, the antennais preferably built in or mounted on the surface in place of theexternally protruding one.

FIG. 6 is a flow chart showing the processing sequence until acommunication of the digital camera 301, printer 401, or storage 501 isestablished in this embodiment. The following explanation will be givenusing FIG. 6 taking the digital camera 301 as an example for the sake ofsimplicity. In this embodiment as well, expression “establish acommunication channel” is used, and it means not only to set a wirelesslink but also to establish a logical channel (network layer or transportlayer in the OSI reference model) to allow data communications betweendevices.

Upon detection of an operation of a button used to establish acommunication channel via the user interface of the digital camera 301(step S601), a timer is set (step S602), a retry count is set (stepS603), and the wireless communication function unit 304 outputs acommunication channel establishment request signal via the RF unit 305(step S604).

It is checked if a communication channel establishment response isreceived from a partner device (step S605). If the communication channelestablishment response is received, a communication channel isestablished with the partner communication device (step S606), thusallowing data communications. On the other hand, if a communicationchannel establishment request is received from a partner communicationdevice (step S607), a communication channel establishment response istransmitted (step S608) to establish a communication channel (stepS606). The control waits for reception of the communication channelestablishment response or request unless a pre-set period of timeelapses before neither of the communication channel establishmentresponse are request are received (No in step S609). If either of thesesignals is received after the pre-set period of time has elapsed, thatis, if the timer has reached a time-out (Yes in step S609), the aboveprocesses are repeated from the communication channel establishmentrequest transmission process (step S604) until the number of retriesreaches the set retry count (No in step S610). On the other hand, if theset retry count has been reached, the communication channelestablishment process is aborted. That is, the control returns to astate before the instruction is input in step S601.

When the control shown in the flow chart of FIG. 6 is applied not onlyto the digital camera but also to the printer or storage as thereceiving side, a communication channel between the digital camera andprinter or storage can be established, and a print or storage processcan be smoothly started.

To explain more simply, a case will be examined below wherein the userwants to print a sensed image stored and held in the digital camera bythe printer via a wireless communication. In this case, the useroperates wireless communication channel establishment operation buttonsof the digital camera and printer within an allowable time period (about10 sec=time-out time×retry count suffice). Since objects to be operatedare only two devices on the information transmitting and receivingsides, even when there are a plurality of printers, only two devices,i.e., the designated digital camera and printer, undergo the processesshown in FIG. 6. Hence, a one-to-one communication is nearly ensured,and smooth communication establishment is made.

When the user makes button operations for wireless communication channelestablishment operations on the digital camera and storage within thelimited time period, a communication channel between these devices canbe established, and a save process of sensed images can be easily done.

In subsequent processes, since the communication channel has beenestablished, the user need only select an image to be printed or saved,and transmits the selected image on the digital camera side, and theprinter prints the received image or the storage saves the receivedimage, as in wired connection. Hence, a description of such processeswill be omitted.

FIG. 7 is a flow chart showing another control of the digital camera,printer, or storage in this embodiment.

The difference between FIGS. 7 and 6 is that a communication unit powerON process (step S704) and communication unit power OFF process (stepS712) are added. By adding such communication unit power supply controlprocesses, power savings of a wireless communication device can beattained. Especially, such control is effective for the digital camera301 which is driven by a battery.

FIG. 8 is a flow chart showing still another control of the digitalcamera, printer, or storage in this embodiment. In this case as well,the flow chart will be explained taking the digital camera as an examplefor the sake of simplicity.

Referring to FIG. 8, upon detection of an operation of a button used toestablish a communication channel via the user interface of the digitalcamera 301 (step S801), a timer is set (step S802), and a communicationchannel establishment request is transmitted (step S803) until the timerreaches a time-out (No in step S805). This communication channelestablishment request may be transmitted once or a plurality of numberof times at given intervals until the timer reaches a time-out. If thetimer has reached a time-out, if no communication channel establishmentresponse is received (step S806) or a plurality of responses arereceived (step S807), error display is made (step S809); if only oneresponse is received, a communication channel is established with apartner wireless communication terminal (step S808).

If the digital camera executes the control shown in FIG. 8, and theprinter side executes the control shown in FIG. 6, when no response isreceived from the printer or when responses are received from aplurality of printers, the digital camera side does not establish acommunication channel as an error, thus prompting the user who operatesthe device to redo an operation. In other words, if the user inputs aninstruction that allows to establish a communication channel with onlyone printer, he or she need not make any operation associated withselection of the printer from the digital camera.

As described above, in order to print a sensed image held in the digitalcamera, the user must operate instruction buttons for communicationchannel establishment operations on two devices, i.e., that digitalcamera and a target printer. Hence, if there are a plurality ofprinters, the digital camera receives a response from only one printer.Therefore, it is nearly unlikely that responses are received from aplurality of printers in step S807 in FIG. 8. It is determined in stepS807 in FIG. 8 that responses are received from a plurality of printerswhen another user happens to issue a wireless print instruction to thedigital camera and printer.

FIG. 9 is a flow chart showing still another control of the digitalcamera, printer, or storage in this embodiment. In this case as well,the following description will be given taking the digital camera as anexample for the sake of simplicity.

The flow chart of FIG. 9 is basically the same as that of FIG. 8, exceptthat if communication channel establishment responses are received froma plurality of devices (step S906), a plurality of pieces of respondingterminal information are displayed (step S907) to prompt the user toselect one of them (step S908), thus establishing a communicationchannel with the selected partner device (step S909).

If the digital camera executes the control shown in FIG. 9, and theprinter side executes the control shown in FIG. 6, when responses arereceived from a plurality of printers, these printers are displayed, andthe user selects one of them. If only one response is received, acommunication channel is directly established without the interventionof the user's selection operation.

FIG. 10 is a flow chart showing still another control of the digitalcamera, printer, or storage in this embodiment. In this case as well,the flow chart will be explained taking the digital camera as an examplefor the sake of simplicity.

Referring to FIG. 10, upon detection of an operation of a button used toestablish a communication channel via the user interface of the digitalcamera 301 (step S1001), a communication channel establishment processis executed according to one or a combination of the control processesshown in FIGS. 6 to 9 (S1002). If photo data to be transmitted to theprinter has already been selected (step S1003) at the time ofestablishment of the communication channel, data is immediatelytransmitted to the printer to which the communication channel has beenestablished (step S1004). After that, every time photo data to betransmitted is selected (step S1005), data is transmitted to thatprinter (Step S1006). The determination process in step S1003 isattained by designating an image to be printed (or a plurality ofimages) before a wireless communication, storing the designation resultin the flash ROM 313 with a predetermined file name, and then checkingif that file is stored. Alternatively, whether or not information thatspecifies an image to be printed is described in a predetermined formatin a predetermined region of the flash memory 313 may be determined inplace of the file name.

According to the above process, the operator of the digital camera 301can start a print process by selecting an image to be printed inadvance, and then inputting a communication establishment instruction toboth the printer and digital camera, thus obviating the need for anywireless communication setup operations.

FIG. 11 is a flow chart showing another control of the printer 401 inthis embodiment. Assume that the printer 401 is connected to a PC or thelike by wire (e.g., the USB interface or the like), and data to beprinted out is also transmitted from that wire.

Referring to FIG. 11, the CPU 415 of the printer 401 determines whetheror not a print request from the wire is detected (step S1101) andwhether or not an instruction button for a communication channelestablishment operation is operated (step S1103). The CPU 415 waits forthe print request or wireless communication establishment instruction.

If it is determined that the print request from the wire is detected(Yes in step S1101), a printout process designated by that request isexecuted (step S1102). If it is detected that the instruction button fora communication channel establishment operation is operated (Yes in stepS1103), a communication channel establishment process is executedaccording to one of the control processes shown in FIGS. 6 to 9 (stepS1104). Only a print process from the wireless communication channel isaccepted (step S1105) before a communication channel disconnectioninstruction button is operated (No in step S1106), and a print requestfrom the wire is not accepted. Note that the printer 401 has thewireless channel disconnection instruction button in the abovedescription. However, the user may instruct a series of printoperations, and disconnection of the communication with the digitalcamera may be used as a trigger.

If the communication establishment process has failed in step S1104,wired connection is enabled, and the flow returns to step S1101 whileskipping steps S1105 and S1106.

In FIG. 11, the operation of the wireless communication channelestablishment operation instruction button is ignored during the wiredprint process. Hence, an example that solves such problem will beexplained with reference to the flow chart of FIG. 12.

Upon detection of the operation of a communication channel establishmentoperation instruction button (step S1201), it is checked if a printoutprocess from a device connected by wire is in progress (step S1202). Ifthe printout process is in progress, the current print data is printedout to where it is convenient (to the end of a page in practice) (stepS1203). At this time, a busy signal is output to the device connected bywire to control it to wait for transmission of the next page. Then, acommunication channel establishment process is executed (step S1204).Only a print process from the wireless communication channel is accepted(step S1205) before that communication channel is disconnected (stepS1206). After the communication channel is disconnected, a ready signalis output to the device connected by wire to continue the print processfrom the wire (if pages to be printed still remain) (step S1207).

If the printer 401 of this embodiment comprises a large-capacity storagedevice (hard disk or the like), the aforementioned busy signal need notbe output. This is because data received via the wire need only besequentially spooled in the above storage device.

Second Embodiment

The second embodiment will be described below. The second embodimentwill explain an example that can facilitate search and selectionprocesses of a partner communication device with which a communicationchannel is to be established even in different networks.

FIG. 13 is a diagram showing an example of the arrangement of a wirelesscommunication system that allows data communications using wirelesscommunication means.

Referring to FIG. 13, digital cameras 1302 and 1303 (their arrangementsare the same as that shown in FIG. 3) comprise wireless communicationfunctions, and form a wireless adhoc network 1301 that makes datacommunications between the digital cameras or with a printer 1304 (withthe same arrangement as in FIG. 4) using the wireless communicationmeans. Also, a digital camera 1306 forms a wireless adhoc network 1305with a printer 1307.

FIG. 14 is a diagram showing another example of the arrangement of awireless communication system that allows data communications usingwireless communication means.

Referring to FIG. 14, digital cameras 1402 to 1404 (their arrangementsare the same as that shown in FIG. 3) comprise wireless communicationfunctions, and form a wireless infrastructure network 1401 which allowscommunications among the digital cameras or with a printer 1406 (seeFIG. 4) or storage 1407 (see FIG. 5) via an access point 1405 using thewireless communication means. Likewise, digital cameras 1409 and 1410form a wireless infrastructure network 1408 with a printer 1412 via anaccess point 1411.

FIG. 15 is a flow chart showing another control of the digital camera,printer, or storage in the second embodiment. The processing sequencewill be explained taking the digital camera as an example for the sakeof simplicity. Assume that a default network setup is set and registeredin advance in the flash ROM (see reference numeral 313 in FIG. 3) of thedigital camera.

Referring to FIG. 15, upon detection of the operation of an instructionbutton for a communication channel establishment operation (step S1501),the CPU of the digital camera executes a communication channelestablishment process based on the default network setup (step S1502).If communication channel establishment process based on that setup hasfailed (No in step S1503), the CPU executes a communication channelestablishment process (step S1505) using another ESSID present on theidentical frequency channel (step S1504). If a communication channelcannot be established even after the process is repeated for allregistered ESSIDs, the CPU aborts the search process in the frequencyband of interest, and checks if another search frequency is available(step S1506) so as to search another frequency. If another searchfrequency is available, the CPU sets that frequency and its first ESSID(step S1507) to repeat the processes in step S1503 and subsequent steps.

When the digital camera executes the control shown in FIG. 15, and theprinter executes the control shown in FIG. 6, even when the digitalcamera and printer are present in different wireless communicationnetworks, a communication channel can be established by a simpleoperation without any setups about the networks.

FIG. 16 is a flow chart showing another control of the digital camera,printer, or storage in the second embodiment. This flow chart will beexplained taking the processes of the digital camera as an example forthe sake of simplicity.

Referring to FIG. 16, upon detection of the operation of an instructionbutton for a communication channel establishment operation in thedigital camera (step S1601), a device search process is conducted usingall frequency channels (channels 1 to 14 in Japan) and ESSIDs (stepS1602). If no device returns a response (step S1603), an error messageis displayed, and the flow ends (step S1608). At this time, a messageindicating a search failure may be displayed.

If one device returns a response (step S1604), a wireless communicationchannel with that device is established (step S1607). If a plurality ofdevices return responses, a list of the devices that respond isdisplayed (step S1605) to prompt the user to select one communicationpartner device (step S1606). Then, a wireless communication channel withthat device is established. That is, if one device returns a response,connection is established to that device without any user'sintervention.

When the digital camera executes the control shown in FIG. 16, and theprinter executes the control shown in FIG. 6, even when the digitalcamera and printer are present in different wireless communicationnetworks, a communication channel can be established by a simpleoperation without any setups about the networks. When the printerexecutes the processes shown in FIG. 16, the digital camera can executethe processes shown in FIG. 6.

Third Embodiment

The third embodiment will be described below. The third embodiment willexplain an example that facilitates search and selection processes of apartner communication device with which a communication channel is to beestablished regardless of the communication mode.

FIG. 17 is a flow chart showing another control of the digital camera,printer, or storage in the present invention. In this case as well, theflow chart will be described taking the digital camera as an example forthe sake of simplicity.

Referring to FIG. 17, upon detection of the operation of an instructionbutton for a communication channel establishment operation of thedigital camera (step S1701), the current operation mode (adhoc orinfrastructure mode) is stored (step S1702), and an adhoc mode is setfirst (step S1703) to execute a communication channel establishmentprocess (step S1704). The process in step S1704 is executed in the adhocmode, but the process itself may be one of those shown in FIGS. 6 to 9.

After a communication channel is established (step S1705), an operationis made in the adhoc mode. If the communication channel is disconnected(step S1706), the control returns to the stored operation mode (stepS1707). Note that the process for transmitting image data from thedigital camera to the printer (or storage) and printing (or saving) thatimage data is executed while No is determined in step S1706.

When the processes shown in FIG. 17 are executed by the digital cameraas the information transmission source and by the printer or storage asthe information receiving side, a communication channel between them canbe smoothly established.

The reason why the sequence shown in FIG. 17 is adopted will beexplained in detail below.

The printer of this embodiment is used in an environment in which itsprint data generation source is not limited to only the digital camera,and receives and prints data from a personal computer (not limited toone computer). Hence, the printer is normally set in a print datareception waiting state in the infrastructure mode via the access point.

According to the sequence shown in FIG. 17, when the user operates theinstruction buttons for a communication channel establishment operationof two devices, i.e., the digital camera and a specific printer, thesedevices are set in a common communication mode, i.e., the adhoccommunication mode to execute a communication establishment process.Hence, a communication channel can be established between these devices,and connection of another device can be excluded.

FIG. 18 is a flow chart showing another control of the digital camera,printer, or storage in this embodiment. In this case, the followingexplanation will be given taking the processes of the digital camera asan example for the sake of simplicity.

Referring to FIG. 18, upon detection of the operation of an instructionbutton for a communication channel establishment operation of thedigital camera (step S1801), the power supply of the wirelesscommunication function unit (304 and 305 in FIG. 3) is turned on (stepS1802), and an adhoc mode is set (step S1803) to execute a communicationchannel establishment process (step S1804). After the communicationchannel is established (step S1805), an operation is made in the adhocmode. If the communication channel is disconnected (step S1806), thepower supply of the communication unit is turned off (step S1807) toattain power savings.

FIGS. 19 and 20 are flow charts showing another control of the digitalcamera, printer, or storage in this embodiment. In the followingdescription, assume that the digital camera (transmitting side) executesthe processing sequence shown in FIG. 19, and the printer (receivingside) executes the processing sequence shown in FIG. 20 for the sake ofsimplicity.

Referring to FIG. 19, if the power supply of the digital camera isturned on and a wireless communication instruction is input or if thepower supply is turned on while a wireless communication instruction isinput by a switch or button, an adhoc mode is set (step S1901), and amessage indicating the adhoc mode is displayed (step S1902). Thismessage may be implemented by various methods such as LCD display, LEDindication, and the like. A communication channel establishment processis executed using communication parameters which are set in advance forthe adhoc mode or are determined to establish a communication channel(step S1903). After the communication channel is established (stepS1904), an operation is made in the adhoc mode. If the communicationchannel is disconnected (step S1905), an infrastructure mode is set(step S1906) to display a message indicating the infrastructure mode(step S1907).

Referring to FIG. 20, if the power supply of the printer is turned on, atimer is set (step S2001), and an adhoc mode is set. At this time, setupparameters to be used are set in advance or are determined to establisha communication channel. Upon reception of a communication channelestablishment request (step S2003), a communication channelestablishment response is transmitted (step S2004), thus establishingthe communication channel (step S2005). If no communication channelestablishment request is received (step S2003), the control waits untilthe timer reaches a time-out (step S2006). If the timer has reached atime-out, the infrastructure mode is set (Step S2007).

In this manner, when the digital camera executes the control shown inFIG. 19 and the printer executes the control shown in FIG. 20, acommunication channel can be easily established by turning on the powersupplies of the digital camera and printer.

FIGS. 21 and 22 are flow charts showing another control of the digitalcamera, printer, or storage in this embodiment. In the followingdescription, assume that the digital camera executes the processes shownin FIG. 21, and the printer executes the processes shown in FIG. 22 forthe sake of simplicity.

Referring to FIG. 21, if the power supply of the digital camera isturned on or if a wireless communication channel establishmentinstruction is input, an adhoc mode is set (step S2101), and a messageindicating the adhoc mode is displayed (step S2102). This message may beimplemented by various methods such as LCD display, LED indication, andthe like. A communication channel establishment process is executedusing all ESSIDs and all frequency channels in the adhoc mode (stepS2103). After the communication channel is established (step S2104), aseries of print processes or storage processes (when the storageprocesses FIG. 22) are executed in the adhoc mode. If the communicationchannel is disconnected (step S2105), an infrastructure mode is set(step S2106) to display a message indicating the infrastructure mode(step S2107).

Referring to FIG. 22, if the power supply of the printer is turned on orif a reception instruction from the digital camera is input, an adhocmode is monitored (step S2202) while setting an infrastructure mode(step S2201). At this time, setup parameters to be used in the adhocmode are set in advance or are determined to establish a communicationchannel. Also, a beacon of the adhoc mode is output if necessary. Uponreception of a communication channel establishment request in the adhocmode (step S2203), the adhoc mode is set (step S2204), and acommunication channel establishment response is transmitted (stepS2205), thus establishing the communication channel (step S2206).

In this manner, when the digital camera executes the control shown inFIG. 21 and the printer executes the control shown in FIG. 22, acommunication channel can be easily established by turning on the powersupplies of the digital camera and printer or inputting a connectioninstruction between the digital camera and printer to them.

Fourth Embodiment

The fourth embodiment of the present invention will be described below.The fourth embodiment will describe an example that automatically setscommunication parameters for an infrastructure mode, and allows wirelesscommunication devices to easily make wireless communications.

FIGS. 23 and 24 are flow charts showing another control of the digitalcamera, printer, or storage of the present invention. In the followingdescription, assume that the digital camera executes the processes shownin FIG. 23, and the printer executes the processes shown in FIG. 24 forthe sake of simplicity.

Referring to FIG. 23, upon detection of the operation of a setup datatransmission button provided to the console (step S2301), the CPU of thedigital camera sets an adhoc mode (step S2302) and executes acommunication channel establishment process (step S2303). After thecommunication channel is established (step S2304), the CPU transmitssetup data for the infrastructure mode (frequency channel, ESSID,encryption key, and the like) (step S2305), disconnects thecommunication (step S2306), and sets the infrastructure mode (stepS2307).

Referring to FIG. 24, upon detection of the operation of a setup datareception button (step S2401), the CPU of the printer sets the adhocmode (step S2402), and executes a communication channel establishmentprocess (step S2403). After the communication channel is established(step S2404), the CPU receives the setup data for the infrastructuremode (step S2405), disconnects the communication in the adhoc mode (stepS2406), and sets the received setup data as communication parameters ofthe infrastructure mode (step S2407), thus setting the infrastructuremode (step S2408).

In this manner, when the digital camera executes the control shown inFIG. 23, and the printer executes the control shown in FIG. 24, thedigital camera and printer can be easily brought in an identical networkin the infrastructure mode.

The first to fourth embodiments have been described. However, thepresent invention is not limited to these embodiments. For example, thepresent invention may be applied to a case wherein a specific button,power switch, specific touch panel switch, or the like is used as meansfor establishing a communication channel. Likewise, embodiments thatadopt, as a wireless communication mode of a wireless communicationdevice, the adhoc mode of a wireless LAN, the infrastructure mode of thewireless LAN, a communication mode such as BLUETOOTH, or the like, andadopt, as wireless communication devices, a digital camera, printer,storage, scanner, data input device, data output device, and the likewhich have a wireless communication function, can be easily implemented.

Combinations of the control processes and devices are not limited to theabove embodiments. For example, the control methods of the digitalcamera and printer may be replaced, or the control method of each of theabove embodiments may be implemented as that for another device. As acommunication mode, the adhoc and infrastructure modes have beenexemplified. However, in terms of control, these two communication modescan be replaced with each other, or communication means other than thewireless LAN such as BLUETOOTH and the like can be defined ascommunication modes.

As described above, according to the embodiments of the presentinvention, when a wireless communication channel is to be establishedupon transmitting an image from the digital camera to the printer (orstorage) and making the printer (or storage) print (or save) that image,even if there are a large number of wireless communication devices, acommunication is more likely to be established to have a one-to-onerelationship, and operations required for the user can be simple.

As described above, according to the present invention, even in anenvironment that includes a plurality of wireless communication devices,since a one-to-one relationship can be set upon establishing a wirelesscommunication between a wireless communication device on the informationtransmitting side and a wireless communication device that receives andprocesses information, simple user's operations can be assured at leastuntil the communication is established.

As many apparently widely different embodiments of the present inventioncan be made without departing from the spirit and scope thereof, it isto be understood that the invention is not limited to the specificembodiments thereof except as defined in the claims.

The invention claimed is:
 1. A wireless communication device comprising:one or more processors; and one or more memories including instructionsthat, when executed by the one or more processors, cause the device to:determine whether an operator has made a first operation forestablishing a communication channel; search, using one of a pluralityof frequency channels in turn, another wireless communication device atwhich a second operation for establishing a communication channel hasbeen made; establish, in a case where the another wireless communicationdevice at which the second operation has been made is detected within apredetermined time period from when the first operation has been made, acommunication channel with the another wireless communication deviceeven if the predetermined time period does not elapse from when thefirst operation has been made, so that a wireless network between thewireless communication device and the another wireless communicationdevice is formed; wherein the predetermined time period is a time periodthat the wireless communication device continues a process forestablishing a communication channel in a case where the anotherwireless communication device at which the second operation forestablishing a communication channel has been made is not detected;receive, from the another wireless communication device on the formedwireless network, a communication parameter including information of anencryption key which is used for a cryptographic communication in aninfrastructure mode of a wireless local area network common to theformed wireless network; and perform processing for the cryptographiccommunication in the infrastructure mode with the another wirelesscommunication device using the received communication parameterincluding information of the encryption key.
 2. The device according toclaim 1, wherein the wireless communication device notifies the operatorof an error in a case where the wireless communication device does notdetect, within the predetermined time period, the another wirelesscommunication device at which the second operation has been made.
 3. Thedevice according to claim 1, wherein the wireless communication deviceestablishes the communication channel with the another wirelesscommunication device without intervention of operation by the operatorafter it is determined that the first operation has been made.
 4. Thedevice according to claim 1, wherein the wireless communication devicetransmits a request signal for establishing of the communicationchannel.
 5. The device according to claim 4, wherein the wirelesscommunication device transmits the request signal a plurality of times.6. The device according to claim 4, wherein the wireless communicationdevice receives a response signal corresponding to the request signal.7. The device according to claim 1, further comprising a timer tomeasure a time elapsed from when the first operation has been made. 8.The device according to claim 1, wherein the wireless communicationdevice is a digital camera capable of capturing an image.
 9. The deviceaccording to claim 1, wherein the communication parameter furtherincludes information of SSID (Service Set Identify).
 10. The deviceaccording to claim 1, wherein the wireless communication deviceestablishes the communication channel with the another wirelesscommunication device even if the another wireless communication deviceis not set as a default.
 11. A method for controlling a wirelesscommunication device, comprising: determining whether an operator hasmade a first operation for establishing a communication channel;searching, using one of a plurality of frequency channels in turn,another wireless communication device at which a second operation forestablishing a communication channel has been made; establishing, in acase where the another wireless communication device at which the secondoperation has been made is detected within a predetermined time periodfrom when the first operation has been made, a communication channelwith the another wireless communication device even if the predeterminedtime period does not elapse from when the first operation has been made,so that a wireless network between the wireless communication device andthe another wireless communication device is formed; wherein thepredetermined time period is a time period that the wirelesscommunication device continues a process for establishing acommunication channel in a case where the another wireless communicationdevice at which the second operation for establishing a communicationchannel has been made is not detected; receiving, from the anotherwireless communication device on the formed wireless network, acommunication parameter including information of an encryption key whichis used for a cryptographic communication in an infrastructure mode of awireless local area network common to the formed wireless network; andperforming processing for the cryptographic communication in theinfrastructure mode with the another wireless communication device usingthe received communication parameter including information of theencryption key.
 12. A non transitory computer readable storage mediumstoring a program to be loaded to and executed by a computer, thecomputer executing the program to execute: determining whether anoperator has made a first operation for establishing a communicationchannel; searching, using one of a plurality of frequency channels inturn, another wireless communication device at which a second operationfor establishing a communication channel has been made; establishing, ina case where the another wireless communication device at which thesecond operation has been made is detected within a predetermined timeperiod from when the first operation has been made, a communicationchannel with the another wireless communication device if thepredetermined time period does not elapse from when the first operationhas been made, so that a wireless network between the wirelesscommunication device and the another wireless communication device isformed; wherein the predetermined time period is a time period that thewireless communication device continues a process for establishing acommunication channel in a case where the another wireless communicationdevice at which the second operation for establishing a communicationchannel has been made is not detected; receiving, from the anotherwireless communication device on the formed wireless network, acommunication parameter including information of an encryption key whichis used for a cryptographic communication in an infrastructure mode of awireless local area network common to the formed wireless network; andperforming processing for the cryptographic communication in theinfrastructure mode with the another wireless communication device usingthe received communication parameter including information of theencryption key.
 13. The device according to claim 1, wherein the formedwireless network, by establishing the communication channel between thewireless communication device and the another wireless communicationdevice, is a wireless network in an adhoc mode.
 14. The device accordingto claim 1, wherein the formed wireless network, by establishing thecommunication channel between the wireless communication device and theanother wireless communication device, is different from a wirelessnetwork in an infrastructure mode.
 15. The device according to claim 1,wherein the wireless communication device disconnects the formedwireless network according to receiving the communication parameter fromthe another wireless communication device.
 16. The device according toclaim 15, wherein the wireless communication device transits from theformed wireless network to the wireless local area network of thecryptographic communication when the wireless communication devicedisconnects the formed wireless network.